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Collaborative Arrangements (Details) - Nova Scotia Power Inc. [Member] - Jointly Owned Electricity Generation Plant [Member] - CAD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Collaborative Arrangements [Line Items] |  |
Utilities Operating Expense, Purchased Power | $ 19 | $ 18
Utilities Operating Expense, Maintenance and Operations | $ 2 | $ 3

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- Definition Amount of operating expense for routine plant maintenance, repairs and operations of regulated operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(b)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Amount of operating expense for purchased power of regulated operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(b)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Details
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